It would be letter B for the first question and the second answer is D. im not sure but i think thats correct.
<span>Answer: an element and a compound.
An element is a pure substance formed by one kind of atoms (element).
A compound is a pure substance formed by several types of atoms(elements) that are connected by chemical bonds.
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<u>Answer:</u> The molarity of calcium hydroxide in the solution is 0.1 M
<u>Explanation:</u>
To calculate the concentration of base, we use the equation given by neutralization reaction:
where,
are the n-factor, molarity and volume of acid which is
are the n-factor, molarity and volume of base which is
We are given:
Putting values in above equation, we get:
Hence, the molarity of in the solution is 0.1 M.